Our restoration project on the West Fork Gallatin River addresses threats to river health in Big Sky.

An extensive study uncovered nitrogen and sediment pollution in the West Fork caused by treated wastewater irrigation on the golf course and damaged streamside vegetation.

In coordination with Big Sky Resort, we worked to alleviate these issues. By replanting streamside vegetation, enhancing wetland areas, and rebuilding streambanks at ten locations along the Big Sky golf course, water quality and fish habitat improved.

Streambank rebuilt during the West Fork Restoration Project using bioengineering techniques.

The Gallatin River Task Force and their volunteers have been amazing partners. The recent completion of a major stream restoration project on the Big Sky Resort golf course will restore valuable streamside habitat, significantly reduce nitrogen and sediment pollution in the West Fork Gallatin River, and enhance the natural beauty of the course for years to come.

Mark Ockey

Water Quality Protection Specialist, Montana Department of Environmental Quality

Pollutants of Concern

The Montana Department of Environmental Quality flagged water quality in the West Fork Gallatin River as impaired due to elevated levels of nitrate and fine sediment, which causes a cascade of negative effects in river ecosystems:

  • Nitrate is an essential nutrient found in fertilizer, animal waste, and wastewater. However, excess nitrate fuels algae growth. When algae dies and decomposes, microorganisms use precious oxygen, which cold water fish and aquatic insects need to thrive. Irrigating the golf course with treated wastewater effluent is a major source of nitrate to the West Fork.
  • Rivers naturally carry rocks, sand, and clay, or sediment. When streamside areas are disturbed, excess sediment erodes into the river. High levels of fine sediment impact trout and insects in many ways, including filling spawning beds, clouding water, and making it more difficult to breathe. Runoff from logging or construction sites carries excess fine sediment.

Plants, like willows, growing around streams and rivers can act as a buffer that improves water quality by using nutrients, trapping sediment, and stabilizing streambanks. Our project restored willows around West Fork to boost the stream’s natural protection.

Gallery of poorly vegetated streambanks along the West Fork Gallatin River.

Project Outcomes

Our project built a man-made wetland, stabilized streambanks, and enhanced streamside vegetation at ten locations along the golf course in an effort to improve water quality and fish habitat.

The project installed:

  • 1,743 feet of streambank to reduce erosion
  • 6,598 willow cuttings to improve water quality and wildlife habitat
  • 270 willows plantings to improve water quality and wildlife habitat
  • 1 man-made wetland to clean and store water
  • 5 interpretive signs to educate the public about river health